Mine excavator-conveyor assembly



March 10, 1970 E. B RAUN EI'AL 3,499,683

I v MINE EXQAVATOR-CONVEYOR ASSEMBLY Filed Jan. 5. 1968 A I k.

.. q ON Q r I N\ m N .l m w r U mfi In ventors: 'Ernsf Braun Ger? Braun By W Attomey United States Patent 3,499,683 MINE EXCAVATOR-CONVEYOR ASSEMBLY Ernst Braun and Gert Braun, Essen-Heisingen, Germany, assignors to Halbach & Braun, Wuppertal-Barmen, Germany, a company of Germany Continuation-impart of applications Ser. No. 626,059,

626,060, and 626,061, all Mar. 27, 1967. This application Jan. 3, 1968, Ser. No. 704,969 Claims priority, application Germany, Jan. 3, 1967,

- H 61,463 (Filed under Rule 47(a) and 35 U.S.C. 116) Int. Cl. E21c 29/44 U.S. Cl. 299-34 5 Claims ABSTRACT OF THE DISCLOSURE A mine excavator with a chain-driven flight conveyor. The conveyor trough has lateral walls forming channels guiding the flights and simultaneously, without the intermediary of any attached rail or other structure, forming guides for a coal-cutting tool having an inwardly open recess complementary to and engaging the lateral wall of the trough while enveloping it at least along three sides, the tool having a foot underlying the lower'leg of the sidewise-turned W-profile forming the trough wall which also rests on the coal-seam floor at this lower leg. At the channels of the W, the cross-section of the profile is reduced to impart an inherent shock-resistant elasticity to the assembly. An inwardly extending flange forms a deflecting surface above the upper leg of the W and may have a formation complementarily mating with a longitudinal formation along the upper leg of the W to prevent lateral separation of the tool from the trough wall.

This application is a continuation-in-part of our applications Ser. No. 626,059 (now U.S. Patent 3,399,757), 626,060 (now U.S. Patent 3,431,024) and 626,061 (now abandoned), all filed Mar. '27, 1967.

Our present invention relates to a scraping conveyor for the excavation of mines and, more particularly, to a coal-excavating-conveyor assembly in which a multiplicity of planing tools are moved against the wall of a mine tunnel to dislodge the rock therefrom and deposit the recovered material upon a conveyor which carries the material away from the mining zone.

In our copending applications Ser. No. 626,059, 626,- 060 and 626,061, we have described and claimed a scraping-conveyer system for mine excavators in the form of an undercutting, sidewall cutting and scraping or chiseling unit which dislodges chunks of coal or other rock material from the walls of a mine tunnel and scoops the dislodged material onto a conveyer through whence the material is carried rearwardly (with respect to the advance of the trough) to transfer the material to mine carriers or other conveyers leading the product from the mine. In application Ser. No. 626,059 we point out that it is desirable to provide the conveyer trough as a scraper-type conveyer which draws the rock along an apron or plate without permitting the materials to accumulate below the scraper flights. In accordance with the principles of that invention, each flight has a concave leading edge facing in the forward direction of motion with a depth of curvature greater than the width of the gaps between adjoining apron sections. This curvature may be defined by a single arc particularly where the flights are attached at their ends only to a single pair of driving chains; in a preferred embodiment, the flights are secured at their centers to a single chain or driving element, each half of a flight lying on either side of the driving element has its own concave leading edge with the vertex of its curvature disposed 3,499,683 Patented Mar. 10, 1970 substantially midway between the driving element and the outer end of the respective flight half. Each conveyer flight, or each of its halves, has a throughgoing bottom recess extending over the major part of its length and defining a profile of inverted U-shape (when viewed in the opposite position of the flight on the upper run of its path). The forward leg of the U, constituting the concave leading edge, contacts the apron surface while the rear leg is somewhat foreshortened to stand clear of that surface during the scraping operation. Thus, the flights are mechanically stable but the possibility of particle accumulation between their undersides and the apron is minimized. At the same time, the curvature of their leading edges tends to concentrate the swept-up mineral chunks at the center of the flight, or of each flight half, and prevents them from migrating outwardly toward the latter conveyer edges.

Another development in the scraper-conveyer structure is described and claimed in application Ser. No. 626,060 which points out that the cutting tool, coal plane or scraper, which is linearly shiftable along the side of the scraper-conveyer trough, should comprise a body with at least two ramp knives, i.e. knives with curved or inclined guiding surfaces for the chunks of mineral to be cut from the wall; these knives are bounded on one side by lateral edges which lie essentially in a common vertical plane and diverge from each other within that plane in the forward direction of the effective stroke of the tool. With a reciprocating tool, these knives will be effective only during every other stroke. The lower one of the ramp knives is generally chisel-shaped and terminates at its front end in a transverse cutting edge, a ramp surface ascending rearwardly from this cutting edge toward a throat Which integrally connects (in one piece) the two knives and is laterally flared for discharging ascending mineral lumps toward the conveyer trough. The upper ramp knives are preferably shorter then the lower one and curves away from the throat toward the common vertical plane in the forward direction. In addition, one or more generally horizontal ripping knives, for chiseling or scraping the coal from the wall of the tunnel, are integral with the two ramp knives and project forwardly and outwardly beyond the aforementioned vertical plane for a distance less than the length of the upper ramp knife. One such ripping blade may lie substantially at the level of the upper edge of a supporting rail extending along the conveyer trough and on which the tool is slidable, the angle of divergence of the two ramp knives being approximately bisecting by the level of the upper edge of the support ramp. The knives, which may be hardened along their cutting edges, may be divided in two symmetrical halves with opposite orientations when the tool is used for reciprocal motion, the parts being hinged together for a limited relative motion so that the drag of the lower longer ramp knife on the underlying coal layer will be reduced during reverse motion; during the forward stroke the wedge shape of the lower ramp knife forces it more firmly into contact with the layer surface on which it rides.

In application Ser. No. 626,061, we have described an improved guide structure for a coal-scraping conveyor trough and tool guide which consists of a rail member forming a pair of laterally open superposed channels to accommodate upper and lower runs of a flexible driving element connected to the planing tools, each cutting tool being slidably mounted upon this rail member and having a dependent shank secured to one of the runs, preferably the lower run, for entrainment by the driving element. The rail member may be constituted by a profiled (preferably extruded) bar whose cross-section has the general form of a W laid on a side; the upper and lower flanges of this profile are formed with lips partly obstructing the mouths of the two channels, the latter being separated by the center web of the W and having secured thereto a flat strip which further obstructs the channels and is in line with the two lips to define with them a pair of parallel slots giving access to the channels, each slot serving for the guidance of alternate links of the endless chain used as the driving element. The driving strip, which in crosssection forms a bar across the middle leg of the W defined by the central web, may be attached to this web with the aid of a set of bolts traversing the web and engaging the edge of the conveyor trough to attach the rail member to said trough at the same time.

In the system of this latter application, the trough has its apron extending along the central web of an inwardly directed sidewise-turned W in the channel of which the upper and lower flights of the conveyor are guided. Thus the bolts attach the tool-guide rail to the lateral channel of the conveyor trough. Further experience with such structures has demonstrated that it is difiicult to attach the tool-guide rail to the lateral walls of the trough so as to render such assemblies practical in most main applications. However, in the absence of a guide rail for the coal-scraping tools, the entire system is strained and problems arise with respect to the guidance of the tools. Priorart systems have also attempted to solve these problems more or less unsatisfactorily because of the tendency of the tool to ride up on its guiding structure or the tendency of finely divided mineral particles to enter crevices of the assembly.

It is, therefore, the principal object of the present invention to provide a scraper-tool conveyor assembly, especially for coal-mine excavators, which will avoid the disadvantages of prior art scraper arrangements and will extend the principles originally set forth in the aforementioned copending applications.

A more specific object of our invention is to provide a conveyor-trough wall structure for flat-type conveyers in which the guide means for mounting scraping tools along the edge of the conveyer is simplified and a more rational function of the tool is possible.

Still another object of this invention is to provide a system for scraping tools and the like in a flat-type mine excavating converter in which the impact and other stresses applied by the tool to the trough is of minimum effect.

These objects and others which will become apparent hereinafter, are attained, in accordance with the present invention, in a flight-conveyer trough of the general character described whose side walls directly form guide rails for the scraping tool and the scraping tool complementarily receives the guide rail or trough wall at least along three sides of a rectangle and the tool omits the swordtype ramp-like blades which engage the undersurface upon which the trough glides. At least one flange of the tool underhangs the guide rails and trough wall and is dimensioned such that its undersurface, when the tool is properly mounted on this rail, is essentially coplanar with the bottom surface of the trough walls. While the tool-guide rail can be provided on only one wall of the trough, in general both trough walls will form guide rails for the tubes.

According to a further feature of this invention, the trough walls are of sidewise-turned W profile whose channels are directed inwardly toward one another and receive the outer ends of the flights drawn across the conveyer apron which interconnects the central web of both Ws. The outer shanks of the W, whose bight portions form a vertical guide wall for the tool, are at least partly paralleled by corresponding guide surfaces of the tool so that these flanges and the base of the W form the three sides of the rectangular guide structure provided by the rail. In this fashion, it is possible to dispense with separately formed rails which must be bolted to the lateral walls of the trough and must be tightly held thereagainst.

The above and other objects, features and advantages of the present invention will become more readily apparent from the following description, reference being made to the accompanying drawing in which:

FIG. 1 is a vertical cross-sectional view of a conveyer trough having a side wall forming a guide rail for a scraper tool in accordance with this invention; and

FIG. 2 is a similar cross-sectional view of another embodiment.

In the following description, reference is made to a conveyer trough along which the flights of a scraper-type conveyer are guided and which forms a guide rail for a scraper tool. This assembly is generally used in an apparatus of the type described in the aforementioned copending applications and involves a modified trough wall and scraper tool. Aside from these modifications, the apparatus and function are identical with those of the copending applications.

In FIG. 1, we show a coal scraper 1 in which the scraping tool 2 has a bottom surface 2a adapted to ride parallel to the floor F of the mine tunnel and an array of chiselshaped blades 2b along its outer flank 20 for engagement with the mineral strata along the walls of the tunnel. As set forth in the aforementioned copending applications, a multiplicity of such tools maybe mounted along the guide rail of a scraper-conveyer trough which is constructed as there described.

The scraper conveyor comprises an apron 3 in the form of a plurality of metal plates which lie generally parallel to the floor of the tunnel and interconnect a pair of turned W-shaped side Walls, one of which is shown at 4. The flights of this conveyor are constructed as described in application Ser. No. 626,059, are represented at G in FIG. 1, and are connected together by a central chain so that the upper reach of the conveyor draws the mineral chunk along the apron 3 to discharge such chunks finally into a mine car or other collector; the lower reach or return stretch of the chain-linked flights runs beneath the apron 3 and is guided by a channel 20 formed in the side walls 4 below the apron 3. A similar guide channel for the outwardly tapering ends of the flights is provided at 21 along the upper surface of the apron 3. The lateral blades of the scraping tool 2 may be constructed as described in application Ser. No. 626,060.

At least one of the lateral walls 4 of the conveyor trough is constituted as a guide rail which carries the scraper tool 2 without a ramplike or swordlike blade support for the latter. The lateral wall 4 comprises a vertically oriented, i.e., sidewise-turned W-profile member which is received in a laterally open channel 2d formed in the inner wall of the tool 2. This channel is of boxlike configuration and supports the tool 2 at least along three sides of a rectangular construction bounded by the dotdash line 2e. The three sides of the trough wall 4 are formed by the horizontal surface 7a of the upper flange or leg 7 of the trough wall 4 and the lower horizontal surface 6a of the bottom leg or flange 6. The surfaces 6a and 7a parallel to one another but perpendicular to the vertical wall 4a connecting the bight portions 20 and 21 and constituting the third wall of the boxlike profile. The tool 2 is provided with a pair of horizontally extending guide flanges 5a and 517, respectively flanking the surfaces 7a and 6a so that the legs 6 and 7 of the W are at least partly embraced by the scraper tool 2.

The leg 6, along its side facing the floor F of the tool, is formed with a footlike profile 9 whose lower surface 9a is substantialy coplanar with the underside 2a of the tool 2 and which forms a recess 8 into which the flange 5b extends in the manner of a toe. Thus the toes 9 and 5b of the wall 4 and the tool 2 rests upon the ground. In the embodiment of FIG. 2, the upper leg 7 of the lateral wall 4 of the conveyor trough is formed along the surface 7a with a longitudinally extending guide rib 10 received in a complementary recess 11 of an overhand forming the flank 5a analogous to the flange 5a of FIG. 1. Because of the beadlike shape of the formation 9 on the one hand and the recess 8 on the other (FIGS. 1 and 2), the trough 3 or 3' rests upon the floor F of the coal seam at its lateral walls 4 or 4' With considerable torsion (twist) resistance. At the same time, the vertical impact action or jamming of the tool 2 or 2' (arrows C in FIG. 1) is taken up by the inherently elastic lateral walls 4, 4' of the trough which, in the vertical direction, can be treated as a corrugated membrane. The elasticity of the side wall 4 is predominantly a result of the reduced cross-sections at the junction of the toe 9a with the leg 6 of the W as represented by the region B and the narrow throat A at the base of the trough 20 of the lower portion of the W.

In the manner described in the aforementioned applications, lugs 13 are carried by the tool 2 or 2' and extend laterally open into a channel 12 receiving the chain which is connected to the lugs 13 and drives the tool 2 or 2. The apron 5a, 5a overlying the upper leg 7, 7 of the trough 4, 4', curves downwardly and inwardly to protect the upper surface of the W and prevent entry of contaminants between the tool and the rail. Furthermore, the ridge prevents lateral separation (arrow D, FIG. 2) during use.

The device as described has the significant advantage that the coal-cutting tools may rest and ride directly on the lateral wall of the trough and the complications which have hitherto required the attachment of other guide rails to the trough wall are eliminated. Furthermore, since the tool partly overlies the trough (i.e. at toes 5b), and both the tool and the lateral wall of the trough rest upon the ground within the outline (dot-dash line E of the trough), there is no torque or torsional stress on the trough even when the tool engages the mineral strata.

We claim:

1. In a mine excavating conveyer apparatus having a flight conveyor forming a conveyor trough with longitudinally extending lateral walls generally parallel to the floor of the seam to be excavated and at least one cutting tool running along the conveyor for dislodging mineral chunks from the seam, the improvement wherein at least one of said lateral walls is formed directly as a longitudinally extending guide rail, said tool being mounted directly upon said rail for displacement therealong, said rail having a side-wise-turned W-profile forming upper and lower channels for guiding the flights of said conveyer, said conveyer trough further comprising an apron secured to the W-profile intermediate said channels, said tool having a recess open in .the direction of said trough and at least partly receiving said W-profile, said W-profile having a lower leg engaging the floor of said seam, an upper leg and a generally vertical bight portion interconnecting said walls and forming the lateral outline of said trough, said recess having walls essentially paralleling said legs and said bight portion, said tool having a toe underlying said W-profile and projecting inwardly beyond the outline of said trough while being substantially coplanar with said lower leg, said lower leg being provided with a toe projecting laterally beyond the toe of said tool and resting upon the floor of said seam, and within a recess receiving the toe of said tool.

2. In a mine excavating conveyer apparatus having a flight conveyer forming a conveyer trough with longitudinally extending lateral walls generally parallel to the floor of the seam to be excavated and at least one cutting tool running along the conveyer for dislodging mineral chunks from the seam, the improvement wherein at least one of said lateral walls is formed directly as a longitudinally extending guide rail, said tool being mounted directly upon said rail for displacement therealong, said rail having a sidewise-turned W-profile forming upper and lower channels for guiding the flights of said conveyer, said conveyer trough further comprising an apron secured to the W-profile intermediate said channels, said tool having a recess open in the direction of said trough and at least partly receiving said W-profile, said W-profile having a lower leg engaging the floor of said sea-m, an upper leg and a generally vertical bight portion interconnecting said walls and forming the lateral outline of said trough, said recess having walls essentially paralleling said legs and said bight portion, said bight portion being provided with a longitudinally extending outwardly open channel adapted to receive a chain for driving said tool, said tool having a lug projecting laterally inwardly into said channel,-said lower leg having a recess along the underside thereof, said tool having a toe projecting laterally inwardly into said recess and underlying said W-profile, said W-profile being of reduced cross-section in the region of its lower channel for imparting resilience to the conveyer trough in the vertical direction, said lower leg being further provided with a toe laterally inwardly from the toe of said tool, said toes being generally coplanar, said tool further comprising an inwardly extending recess overhanging said W-profile and sloping downwardly and inwardly to deflect chunks of mineral into the trough.

3. The improvement defined in claim 2 wherein said W-profile is formed integrally in a single piece.

4. The improvement defined in claim 2 wherein said upper leg of said W-profile is formed with a longitudinally extending, upwardly projecting ridge, said upper flange having a downwardly open groove slidably receiving said ridge.

5. The improvement definedin claim 4 wherein said ridge of rectangular cross-section.

References Cited UNITED STATES PATENTS 3,164,412 l/1965 Hauschopp et a1 29934 3,372,956 3/1968 Heyer 299-34 FOREIGN PATENTS 1,229,971 12/ 1966 Germany.

649,961 2/ 1951 Great Britain.

ERNEST R. PURSER, Primary Examiner 

